I agree parallel charging and then series discharging would elimanate the imbalance issues and there are a few who take that approach.
Thread here shows alternate connectors .
There are a few problems with this arragement for many however.
Many LiPoly cells are not available as single cells and even the ones which are are often higher than the same cells pre assembled in a pack.
Many Electri Flyers are not DIY types and do not wish to learn have to assembley their own packs. Many do not even want to try to add leads / connectors for checking or balancing Series wired packs.
If you are using larger packs such as 5S 3P or larger there are just to many connectors to be bothered with. Each connector and ssociated length of wire adds resistence to the pack and provides another potentical failure point.
Last on the problem list is the fact that there are no small ,portable, 4.2volt very high amp out put chargers available.
To charge a 3 ,1500 mAh cells in paralle at 1C requires 4.2 volts at 4.5 Amps. . To charge a 5S 3P 6000 pack at would require a 4.2 volts , 30 Ah power source / charger.
Even luc who hase been an advocate of parallel charging ,series dicharging has now stated that with the Thunder Power Smart Balance that he is going to using series charing and using the TP-205 to maintain cell balance.
LLinks to paralle charging/series discharging, Suzanne,Baldwin and TP Balancers.